Dental chair.



PATENTED DEG. 1o, 1907.

' A. W. BROWNE.

DEN

APPLICATION FILED SEPT. 19, 1906.

TAL CHAIR.

PATENTED DEG. 10, 1907.

A. W. BROW-NE. DENTAL CHAIR.

APPLICATION FILED sEPT.19, 190e.

4 SHEETS-SHEET 2.

PATBNTED DEG. 1o, 1907..

A. W. BROWNB.

DENTAL CHAIR.

APPLICATION FILED s121219, 1906.

4 SHBBTSAHHT s.

Wim

PATENTED DEC. l0, 1907.

A. W. BROWNE. DENTAL CHAIR.

APPLIOATION FILED SEPT. 19, 1906.

4 SHEETS-SHEET 4.

MW I w UNITED sTATEs PATENT oEEroE.

ARTHUR W. BROWNE, OF PRINCE BAY, NEW YORK, ASSYIGrNORA TO THE S. S. WHITE DENTAL MANUFACTURING COMPANY, OF PHILADELPHIA, PENNSYLVANIA.

DENTAL CHAIR.

Specification of Letters 'Patent Patented Dec. 10, 1907.

Application filed September 19.1906. Serial No. 335.189.

new and useful Improvements in' Dental Chairs and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled inthe art to Awhich it appertains to make and use the same.

My invention relates to hydraulic supporting and elevating mechanism particularly designed for dental chairs, my object being to improve such mechanism in several particulars. j

The present invention consistsj of certain improvements fully described in the following specication in connection with the accompanying drawings, and ointed out in the claims at the conclusion o said specification.`

In saiddrawings, which illustrate a structure embodying my improvements, Figure 1 (Sheet 1) is a view partly in side elevationv v and partly in central vertical section of the l nections being omitted in this view to avoidchair' base, the pump and its operating conconfusion, and the extensible columnbeing partly `extended.V Fig. 2 (Sheetl) is aview of said base in vertical central section on theA line 2 2 of Fig. 4. Fig. 3 (Sheet 2) 'is a viewv in central vertical section on the line 3-.3 of

Fig. 4, some ofthe `parts being omitted and in vertical section showing the extensible column being extended almost toits highest elevation. Fig. 4 (Sheet 3) is a top or plan view. Fig. 5 (Sheet 3) is a View in horizontal section on the line 5-5 of Fig.

1. Fig. 6 (Sheet 3) is a view in horizontal' section on the line 6-6 oi Fig. 1. Fig. 7 (Sheet 1) is a partial view in vertical section showing the ump and the rigid guide projection 25.. ig. 8y (Sheet 1) is a partial view the opposite or adjustable guide projection 26.A Fig. 9 (Sheet 4) is a view on a larger scale than the preceding views of the lowering valve o eratin mechanism, showing the valve c osed. Fig. 10 (Sheet 4) is a similar view showing the valve open. Fig. 11 (Sheet 4) isa view\ with the parts in the same position as in Fig. 9, but turned at a right angle thereto. Fig. 12-(Sh eet 4) is a partial view similar to'Fig. 11 but showing the valve open. Fig. 1 3

(Sheet 4) is a plan view of the lowering valve. Fig. 14 (Sheet 2) is a viewof the inner Jface of the lever forming part of the lock betweenv the rotatable supporting cylinder and pedestal.

The supporting and elevating mechanism,

which may be regarded as thebase portionvof a dental or other chair, as usual in chairs of the type to which my invention belongs, comprises aA stationary or non-rotating pedestal 1 provided'with a closed bottom 2 and an annular or disk portion 3 for resting upon theoor; a supporting cylinder 4 rotatably mounted in the pedestal; anexten'sible chair- .body supporting and, elevating column 19,

20 and 21, and mechanism'contained in said supportingcylinder 4 for elevating and lowerlng said column.

The Afirst part of my invention to be herein described is the improved -lock betweenthe j i upper and lower bearing surfaces 6 and y7 bei ing also provided between the cylinder and pedestal. The lock, `best shown in Figs. 3 and 14 (Sheet 2) consists of a lever 8 placed vertically between the pedestal and cylinder in a recess 9 of the latter, the lower end of the lever bearing at 10 upon the cylinder, while near its upper end it bears upon the upper bearing 6 of the pedestal. bolt 11 passes loosely through an opening 12 in the lever above the bearing 6 and projects outside the base through an opening or bearing in the dome or upper part 14 of the cylinder. The outer end of the screw-bolt is engaged by an operating handlevorlever 15, by means of which the lever 8 may be drawn against the pedestal and the cylinder and A headed screw chair-bod securely locked against rotation.

A, very s ight movement of vthe operating handle or lever 15 is required to clamp or release the cylinder. It' will be observed that the lever 8 is held in position solely by the screw-bolt 11, the lever not being connected in any other'wayeither to the pedestal or cylinder. On theinner face of the lever 8 is a series lof notches 16 (see Fig. 14) to be engaged' by a lug or lugs formed in this instance by ,a pin 17 passed through the screw-bolt.

This construction aHords means for adjusting the operating lever 15 to diHerent positions.

If desired a light plate spring 18 may be employed for yieldingly holding the lever in .proper position, the lower bent end of the 21, upon -the upper end of which the chairsection or cylinder 20 entering the cylinder I' vwear of the parts.

f cy inder, [whereby said amount o f iiexibility, su

the' purpose in view.` Screws 30,30 serve to.` regulate theposition of the p late and projection carried thereby, thus securing the properl body is mounted by way of a cross-head or yoke, not shown.. The main section 19 is elliptical in cross-section and is divided` into two parallel cylinders 22 and 23, the fixed 22 and the plunger section 21 being iitted in the `cylinder 23. i

A peculiarity of the main section 19 of th supporting column is that it has bearing in the supporting cylinder at only twopoints which are di'ametrically opposite'eaoh other on the fiat side of the ellipse midway the long j axis thereof. In the present instance these bearings consist of preferably half round longitudinal grooves 24, 24, one on each side of the main section, which are engaged bycorresponding projections 25 and 26 of the suplporting cylinder, the upper endof which is contracted into a'n'eckfportion 27 elliptical in -cross section to correspond with the cross section of the main section of the supporting column. The projections 25,26, must be formed on some part' of or have some con.- nection with the supporting cylinder and at least one of said projections should be mov-- able or adjustable toward and away from the column, in order to' hold the column with sufiicient'firmness while permitting it to slide freely up and down, and also tovprovide for of supporting said projections is to form them upon plates 28 and 29 cast inte al with the cylinder. One of said plates (28 is cast rigid with the cylinder and' is therefore immovable, but the other (29) is connected with lsaid cylinder'only atits opposite ends, .the

to and bottom being Ldisconnected from the fphilatelies a limited amount of friction between 'the column and cylinder. Ifdesired the plate 29 or the projection 26 may be madeadjustable in some' other manner.

The plun er 2'1 is formedwith a ybali-roundlongitudina groove 31 in which'fits a correspondingly shaped projection carried by the main section 19 of the column. This pro- 'jection (see Fig. 3, Sheet 2) may consist of a The preferred inanner ieee. iormed at one end. with a head 49 V hay/'ing bearing in the supporting-cylinder and provided with an opening 5() in which the ref. cient, however, for

block or shoe 32 half round-in cross section and provided with a rounded projection-34 seatedin the socket of. an adjustablebearing formed b a screw 33 in the main section 19.

Suitab e packing 35 is placed between the fixed cylinder 20 andthe cylinder 22 of the main section of the column, and also at 36 between the plunger 21 and the cylinder 23 of said main section. The upper end of the cylinder 22 is closed by a screw plug 37 and the lower end of the cylinder 23 is closed by a screw cap-38.

Communication between the two cylinders 22 and 23 is afforded by a passageway 39 at the lower end of the main section of the column. ,The fixed cylinder 20 communicates by way offa passage 40 with a pump indicated at 411, which is operatedfby an external foot lever 42.

.Oil may be introduced to the base through l an opening in l'the plug 37, which opening is closed by a screw 43. 2 By operating -the pump oil is forced into the fixed cylinder 2O y .and from thence into the cylinder,22 and-.next

into the cylinder 23, with'the result ofpro v jecting vor extending the column. That is-to say, the main section 19 is projected u wardly in the supportin cylinder-4 and t e plunger 21,v is main section. y opemng a lowering valve, furtherv on to be explained, the column and the chair-body carried thereby may be lowa ered.

The pump: (see "Figs-z'. 2 and 7, Sheetl, and Fig. 6, Sheet 3) consists .of an upright cylinder 41, a hollow piston 44, a piston rod 45, a

rocking arm 46, a rockshaft 47 `to'which said grojecte upwardly in` said arm isl rigidly connected, the before-mentioned operating foot lever 42, and a spring 48 for returning the parts to their normal pov sition. The rocking arm 46 is mounted in bearings in the dome 14 ofthe supportin cylinder 4, and in order that the rocksha t may be quickly 'and easily'assembled and at the same time a strong durable connection be provided, the constructin is as follows: The operating foot lever 42 and the rockshaft 47 are integral, while the arm 46-is a separate (See Fig. 6, Sheet 3.) This arm 46 is duced 'end 51 -of the rockshaft 47 is snugly fitted. Formed on the'opposite end of the rockshaftis a journal 52' having bearin in the supporting-cylinder and correspon ing to the. journal formed by the head 49 of .the

arm 46. A lug 53 on the arm 46 engaging a notch or socket-in the rockshaft causes'said rockshaft and-arm to moveas one, while a screw 54 securely binds the .two together. The parts are readily' assembled; by first vplacing the arm in position, then'insertmg the rockshaft through the bearinf` of cyl1nder'4 and through the opening 50 of the' .arm until the lug 53 is seated' in the rockshaft notch,

.and nally placing the screw 54 in position.

Fig. 6, Sheet 3 and Figs. 9, 10,11, 12 and 13,

' j necessity of keeping the foot upon said lever.

Voil in the xed cylinder.

a depression 62 on the top of the bell-crankv lever 5.8 is connected at its upper end at 66 to y cylinder dome. by way of a link 69 is a vertical release rod 70 adapted to project above the supporting cyl- Sheet 4. An outwardlyopening coned valve 57 is located in a passageway at the lower end of the xed cylinder 20, the valve being connected to a bell-crank lever 58 fulcrumed at 59, a sti coiled spring 60 serving to normally close the valve against pressure of the A rod 61 resting in an arm 63 fast u'pon a rockshaft 64 having bearing in the supporting cylinder 4. This rockshaft projects outside said cylinder above the pedestal .1 and has there connected with itv an 'operating or trip lever or handle 65 designed to be actuated by the foot.. Nor.- mally the trip valve is closed by reason of the spring 60, but by slightly moving the trip' leverv to one side the rod 61 is depressed, thus rocking the bell-crank lever 58 and opening the valve'against the pressure ofthe spring 60, whereby the oil is allowed to escape from the Jfixed cylinder 20 and the column and chair-body allowed to descend.

arm 63 is so related to the rockshaft 64 that if the trip lever 65 is moved far enough to cause said connection 66 to pass beyond a line drawn through the center of the rockshaft and the lower end of the rod 61, the

.trip valve will be held open until the parts its lowest position by merely pressing theA trip lever as far as it will gol and without the When the trip lever has been pushed ar enough to hold the valve open, as just described, its further movement in this direction is arrested by an arm 67 coming in contact with a fixed stop formedin this instance by a lug 68 on the plate 29 of the supporting Connected to said arm 67 inder dome. When the trip lever is moved to hold the trip valve open the release rod is thrust upwardly, and when thechair-body reaches its lowest 4position a lug on the crosshead or yoke (not shown)strikes the release rod, thus automatically closing the trip valve andrestoring the trip lever to its normal position. This constructionv is a simplification of the mechanism shown, described and claimed in Amy United States Letters Patent No. 713,282, granted November 11, 1902.

The lower end of the' release rod 70 may be upon said pedestal and also through an opening or bearing insaid supporting-cylinder,

and an operating handle havingthreaded connection with said screw-bolt outside said supporting-cylinder.

2. The combination m a chair base, of the supporting cylinder, any extensible chairbody supporting column, the main section of said column having an elliptical cross-section, said main sectionhaving bearing in the supporting-cylinder at but two points diametrically opposite each other on the flat side of the ellipsemidway the long axis thereof.

' 3. The combination in a chair base, of the supporting cylinder, an extensible chair- .n body supporting column, the main section of The connection 66 between the rod 61 and said column'having an elliptical cross-section, centrally disposed longitudinal groovesdiametrically opposite each other on the flat sides of said main section, and corresponding projections onl said supporting-cylinder, said projections iitting in said grooves.

4. The combination in a chair supporting; cylinder, an extensible chairbody supporting column, the main section of said column having an elliptical cross-section, centrally disposed longitudinalv grooves diametrically opposite each other on the liat sides of said main section, and corresponding projections mounted upon said supportingcylinder and fitting said grooves, one of said projections l being adjustable toward and away from said main section."

5. The combination in a chair base, of the supporting-cylinder, an extensible chairbody supportin column movable up and down in said cy nder, longitudinal grooves on `the exterior of said column, lates integral with said cylinder, one of said plates be- .ing slightly flexible or movable toward and away from said column, a projection on each of said plates, each projection fitting agroove in said column, and means for altering the position of said movable late. 6. The combination in a chair ase, of the supporting cylinder, an extensible chairlbody su porting column, the main section of said co umn having an elliptical cross-section, centrally disposed longltudinal grooves diametrically Opposite each other on the .flat

base, of the sides of said main section, a pair of plates integral with said sup orting-cylinder, one `oi" sald plates being sllgV tly flexible or movable toward and away from said main section, a rojection on each of said plates adapted to t in the corresponding roove on the main section, and' means' for aItering the position of said movable plate. .I

7. In sup orting and elevating mechanism for`chairs, te combination of an extensible column, mechanism for elevating or extendingsaid column, a normally closed Aoutlet or lowering valve, a bell-crank lever connected to said valve, arockshaft, an actuating lever connected thereto, an arm also connected to said rockshaft, and a rod connected with said arm and with said bell-crank lever of the out-v let or lowering valve.

8. In sup orting and elevating mechanism forchairs, t e combination of an extensible column, mechanism for elevating,l said column, a normally closed outlet-or lowering valve, a rockshaft, an actuating lever connected thereto, an arm also connected to saidshaft, a rod pivoted to 'said arm and having connection with said outlet or lowering valve, another arm connected to said rockshaft, and a vertically movable trip rod having connection with said last mentioned arm.

9. The combination in a chair base, of a edestal, a supporting-cylinder, an extensible column, a ump, a rocking arm having connection witii) the piston of said pump, sal rocking arm being provided with a head at one end having bearing in said supportingcylinder and formed with an' opening, a rockshaft having one end fitted in the o en ing 'of said' rocking arm and having'bearing atits oppositevend in said supporting-cylinder, an

ARTHUR w. BRowNn.

signature Witnesses: A

SEYMOUR CASE, l M. E. DERIcKsoN.

operating-lever rigidly projectingfrom saidV 

